<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<script type="text/javascript" src="js/jquery-1.11.1.min.js"></script>
		<script type="text/javascript">
			$(function(){
				$("input").click(function(){
					//is()函数用于检测某个元素，是否具有指定的身份
//					console.log(  $("#box1").is(".hehe") );
//					console.log(  $(".hehe").is("#box1") );
					
					//is()括号里面，可以写jQuery自定义的冒号伪类
					$("ul li.last").css("background","yellowgreen");
					console.log(  $("ul li.last").is("li:last") );//输出为false，因为最后一个li是44
				});
			});
		</script>
	</head>
	<body>
		<input type="button" value="点我" />
		<ul>
			<li>11</li>
			<li>22</li>
			<li>33</li>
			<li class="last">5555</li>
			<li>44</li>
			
		</ul>
		
		<div id="box1" class="hehe">
			
		</div>
		<div class="hehe">
			
		</div>
	</body>
</html>
